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  <title>Boost Escaped List Separator</title>
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  <h1 align="left"><img src="../../../boost.png" alt="C++ Boost" width="277"
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  <h1 align="center">Escaped List Separator</h1>

  <div align="left">
    <pre>
escaped_list_separator&lt;Char, Traits = std::char_traits&lt;Char&gt; &gt;
</pre>
  </div>

  <p>The <tt>escaped_list_separator</tt> class is an implementation of the
  <a href="tokenizerfunction.htm">TokenizerFunction</a>. The
  escaped_list_separator parses a superset of the csv (comma separated value)
  format. The examples of this formate are below. It is assumed that the
  default characters for separator, quote, and escape are used.</p>

  <p>Field 1,Field 2,Field 3<br>
  Field 1,"Field 2, with comma",Field 3<br>
  Field 1,Field 2 with \"embedded quote\",Field 3<br>
  Field 1, Field 2 with \n new line,Field 3<br>
  Field 1, Field 2 with embedded \\ ,Field 3</p>

  <p>Fields are normally separated by commas. If you want to put a comma in a
  field, you need to put quotes around it. Also 3 escape sequences are
  supported</p>

  <table border="1" summary="">
    <tr>
      <td>
        <p align="center"><strong>Escape Sequence</strong></p>
      </td>

      <td>
        <p align="center"><strong>Result</strong></p>
      </td>
    </tr>

    <tr>
      <td>&lt;escape&gt;&lt;quote&gt;</td>

      <td>&lt;quote&gt;</td>
    </tr>

    <tr>
      <td>&lt;escape&gt;n</td>

      <td>newline</td>
    </tr>

    <tr>
      <td>&lt;escape&gt;&lt;escape&gt;</td>

      <td>&lt;escape&gt;</td>
    </tr>
  </table>

  <p>Where &lt;quote&gt; is any character specified to be a quote
  and&lt;escape&gt; is any character specified to be an escape character.</p>

  <h2>Example</h2>
  <pre>
// simple_example_2.cpp
#include&lt;iostream&gt;
#include&lt;boost/tokenizer.hpp&gt;
#include&lt;string&gt;

int main(){
   using namespace std;
   using namespace boost;
   string s = "Field 1,\"putting quotes around fields, allows commas\",Field 3";
   tokenizer&lt;escaped_list_separator&lt;char&gt; &gt; tok(s);
   for(tokenizer&lt;escaped_list_separator&lt;char&gt; &gt;::iterator beg=tok.begin(); beg!=tok.end();++beg){
       cout &lt;&lt; *beg &lt;&lt; "\n";
   }
}
</pre>

  <p>&nbsp;</p>

  <h2>Construction and Usage</h2>

  <p>escaped_list_separator has 2 constructors. They are as follows</p>
  <pre>
explicit escaped_list_separator(Char e = '\\', Char c = ',',Char q = '\"')
</pre>

  <table border="1" summary="">
    <tr>
      <td>
        <p align="center"><strong>Parameter</strong></p>
      </td>

      <td>
        <p align="center"><strong>Description</strong></p>
      </td>
    </tr>

    <tr>
      <td>e</td>

      <td>Specifies the character to use for escape sequences. It defaults to
      the C style \ (backslash). However you can override by passing in a
      different character. An example of when you might want to do this is
      when you have many fields which are Windows style filenames. Instead of
      escaping out each \ in the path, you can change the escape to something
      else.</td>
    </tr>

    <tr>
      <td>c</td>

      <td>Specifies the character to use to separate the fields</td>
    </tr>

    <tr>
      <td>q</td>

      <td>Specifies the character to use for the quote.</td>
    </tr>
  </table>

  <p>&nbsp;</p>
  <pre>
escaped_list_separator(string_type e, string_type c, string_type q):
</pre>

  <table border="1" summary="">
    <tr>
      <td>
        <p align="center"><strong>Parameter</strong></p>
      </td>

      <td>
        <p align="center"><strong>Description</strong></p>
      </td>
    </tr>

    <tr>
      <td>e</td>

      <td>Any character in the string e, is considered to be an escape
      character. If an empty string is given, then there are no escape
      characters.</td>
    </tr>

    <tr>
      <td>c</td>

      <td>Any character in the string c, is considered to be a separator. If
      an empty string is given, then there are no separator characters.</td>
    </tr>

    <tr>
      <td>q</td>

      <td>Any character in the string q, is considered to be a quote. If an
      empty string is given, then there are no quote characters.</td>
    </tr>
  </table>

  <p>&nbsp;</p>

  <p>To use this class, pass an object of it anywhere in the Tokenizer
  package where a TokenizerFunction is required.</p>

  <p>&nbsp;</p>

  <h2>Template Parameters</h2>

  <table border="1" summary="">
    <tr>
      <th><strong>Parameter</strong></th>

      <th><strong>Description</strong></th>
    </tr>

    <tr>
      <td><tt>Char</tt></td>

      <td>The type of the elements within a token, typically
      <tt>char</tt>.</td>
    </tr>

    <tr>
      <td>Traits</td>

      <td>The traits class for the Char type. This is used for comparing
      Char's. It defaults to std::char_traits&lt;Char&gt;</td>
    </tr>
  </table>

  <p>&nbsp;</p>

  <h2>Model of</h2>

  <p><a href="tokenizerfunction.htm">TokenizerFunction</a></p>

  <p>&nbsp;</p>
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  <p>Revised 
  <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->25
  December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38518" --></p>

  <p><i>Copyright &copy; 2001 John R. Bandela</i></p>

  <p><i>Distributed under the Boost Software License, Version 1.0. (See
  accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
  copy at <a href=
  "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p>
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